Regeneration and genetic engineering of a tropical tree, Azadirachta excelsa
<i>Azadirachta excelsa</i> belongs to the family Meliaceae and is one of the most important silviculture trees in the tropics. In this study, we established a somatic embryogenesis system and succeeded in construction of transgenic lines expressing genes for <i>Bar</i>, <i>GUS</i> and <i>GFP</i> employing the <i>Agrobacterium</i>-mediated transformation technique. Somatic embryos were obtained after approximately two months of culture on Murashige-Skoog (MS) medium containing 5 μM 6-benzyladenine. Plantlets were then regenerated by transferring somatic embryos to modified 1/2 MS medium without phytohormones. We initially attempted genetic transformation using two different <i>A. tumefaciens</i> strains, and found only the strain LBA4404 to be active in infection to explants. The strain EHA101 was totally inactive, suggesting that a specific interaction between <i>Agrobacterium</i> sp. and host plant might be critical for gene transfer. The possibility is discussed of applying the methodology developed in this work to the practical propagation of tropical trees.
- Plant biotechnology
Plant biotechnology 23(1), 123-127, 2006-03-01
Japanese Society for Plant Cell and Molecular Biology